How Authentication works with MoinMoin

MoinMoin historically has supported only username/password authentication and cookie-based sessions: you log in via the login form, moin sets a cookie and from then on this cookie is used for authenticating you - until you log off and the cookie gets deleted (or until the cookie expires).

In many environments this is often not optimal as access restrictions should be based on other user databases like LDAP (Active Directory). Hence, modular authentication was developed for MoinMoin. You use the auth configuration value to set up a list of authenticators that are processed in exactly that order.

When an external user database is used you do not want to recreate all users in moin. For this case the authenticator objects which support user profile creation/updating have a parameter autocreate. If you set it to True a new user profile will be created/updated automatically when a (new) user has passed authentication.

HTTP Basic (but does not request authentication by header, so this is currently only useful for automated stuff, not for browser use; uses Moin's internal user database but on its own does not allow signing up, hence only useful together with MoinAuth)

MoinMoin.auth.http.HTTPAuth

IIS

HTTP Basic, SSPI (aka NTLM), (?)

MoinMoin.auth.http.HTTPAuth, (?)

Other pseudo-authenticators

These are not strictly authenticators, as they don't authenticate users, but use auth information for other purposes:

MoinMoin.auth.log.AuthLog

will just log login/logout/request, nothing else

MoinMoin.auth.smb_mount.SMBMount

mount some smb share using user/password from login, umount on logout

Shipped plugins

MoinAuth (default)

This is the default auth list moin uses (so if you just want that, you don't need to configure it).

HTTP authentication

For HTTP basic auth used with a web server like Apache, the web server handles authentication before moin gets called. You either enter a valid username and password or your access will be denied by the web server.

Moin's HTTP authenticator will just check if user authentication happened and allow access if it has and a valid user is found for the given username.

Unfortunately, it is a bit more complicated:

For Twisted servers the authenticator uses the username and password stored in the moin user profile and allows users to change them both.

For NTLM and Negotiate, it splits off everything before the last backslash ("\") (usually it is "Domain\username") and we also use title() to normalize "username" to "Username".

The only supported PHP application is eGroupware 1.2 currently. But it should be fairly easy to add a few lines of code that extract the necessary information from the PHP session, if you do that, please open a feature request with a patch.

OpenID (with BotBouncer)

The OpenID authentication plugin allows users to sign in using their OpenID and connect that OpenID to a new or existing Moin account. To allow users to sign in with OpenID, add the plugin to the auth list, or to require OpenID with http://botbouncer.com/ verification use:

OpenID authentication requires anonymous sessions, set anonymous_session_lifetime to anything bigger than zero. See HelpOnConfiguration for more details on the value. For OpenID, very little time should be sufficient.

Advanced OpenID RP configuration

The OpenID RP code can also be configured for two use cases:

You can force a specific provider to be used, there are two ways to achieve this:

Simply configure the OpenIDAuth authenticator like this:

auth = OpenIDAuth(forced_service='http://myopenid.com/')

Create an OpenIDServiceEndpoint object and use that for the forced_service parameter:

You can specify functions to be called in various steps of the OpenID authentication process to, for example, implement Attribute Exchange. For now, this is not documented here, you'll have to look at the file MoinMoin/auth/openidrp.py.

LDAP based user authentication

The LDAP authenticator of Moin enables single-sign-on (SSO) - assuming you already have a LDAP directory with your users, passwords, email adresses. On Linux this could be some OpenLDAP server, on a Windows server (usually the domain controller) this is called "Active Directory" (short: AD).

It works like this:

User enters his name and password via moin's login action and clicks on the login button.

On login, ldap_login.LDAPAuth checks username/password against LDAP.

If username/password is ok for LDAP, it creates or updates a user profile with values from ldap (name, alias, email) and creates a user object in the MoinMoin process, then it hands over to the next authenticator...

If username/password is not ok for LDAP, it vetoes and aborts the login (no other authenticators checked).

If the login was successful, moin establishes a session for that user.

LDAP auth installation / configuration

You need to install python-ldap module (and everything it depends on, see its documentation).

You need an LDAP or AD server.

See wiki/config/more_samples/ldap_wikiconfig_snippet in your moin dist archive for a snippet you can use in your wiki config.

Please also read the README file in that directory.

LDAP auth Problems?

MoinMoin support does not know your LDAP server setup, so please follow these steps before asking for help:

Configure DEBUG logging for MoinMoin.auth.ldap_login and look into the log output.

In that case, any client certificates that the user provides will be used to log him on, but if they do not provide one they still have the option of logging on with their username/password.

Writing your own authenticator

See the commented config file fragment contrib/auth_externalcookie/ and MoinMoin/auth/*.py in your moin distribution archive for examples of how to do authentication. Also, the docstring in MoinMoin/auth/__init__.py contains an explanation of what can be done and how it is achieved.

Authenticators can

use the regular login form as their user interface for entering name and password

use the regular logout action for logging out

prohibit logging out (like SSL client certificate authentication that checks for every request)

search existing user profiles for a "matching" user (the match needs not be the name, it can also be the email address or something you put into aliasname)

create a user object and let it remember what attributes were determined by authenticator (and thus should not be offered on user preferences)